General habilitation

- ECDHE-RSA-AES256-GCM-SHA384 is a TLS cipher suite, not a main channel cipher.
  Supply a reasonable default.
- Add control over TLS cipher a give is a modern secure default; credit to
  https://hynek.me/articles/hardening-your-web-servers-ssl-ciphers/
- Straighten out the parameter names and usage for tls-auth, which isn't really
  even related to auth.
Release 0.2.0